We all know thermal conductivity / diffusivity of solids (metals, insulators, semiconductors) is a function of temperature. However, does it depend on mechanical stress, e.g. uniaxial? Has someone ever measured this?
UPD: I have actually just seen some papers on the stress dependence of thermal conductivity in semiconductors (e.g. Ramdane, A., Salce, B., & Challis, L. J. (1983). Stress dependence of the thermal conductivity of Cr-doped GaAs. Physical Review B, 27(4), 2554.); I think it's more or less clear that stress changes the density of electrons in the conduction band and hence the effect. However, it's not clear to me whether there is any effect of stress on the thermal conductivity of metals where the electron density is much greater than for semiconductors and the Fermi surface is simply spherical. Any thoughts on this?
I would say these kinds of studies will be very difficult to conduct. I don't think there is much data about correlations between mechanical stress and temperature parameter.
But, Yes, defenitevely Thermal Conductivity in materials would vary with the conditions of mechanical stress and strain. But I would say, it depends in a large extent on the kind of material.
The correlation should be stronger in semiconductors and insulators, since in these materials the fraction of thermal conductivity due to phonons is much larger than the fraction due to electrons. So, if you modify the lattice structure of a material at its microscopic level, surely this will alter the modes of vibration and alter the phonon's dispersion curves ...
remember in these materials the Thermal Conductivity due to phonons is equal to :
kL = (1/3)*rho*vsound*cv*Lambda
KL =Lattice Thermal Conductivity
rho = Bulk Density
vsound = the Speed of sound in the material, which is equal to the dw/dk of the phonons dispersion curves
cv = Specific Heat at constant volume.
Lambda = Mean free Path of Phonons
Thermal conductivity refers to the intrinsic ability of solids to ensure that products behave as expected when subjected to thermal stress. Thermal stress is stress created by any change in temperature to a material. ... This type of stress is highly dependent on the thermal expansion coefficient which varies from material to material. In general the larger the temperature change, the higher the level of stress that can occur.
Please look at the following below links which may help you in your analysis:
http://www.homepages.ed.ac.uk/chall/PM2/PM2-Ch3.pdf
https://www.eolss.net/Sample-Chapters/C05/E6-178-04-00.pdf
http://webserver.dmt.upm.es/~isidoro/ot1/Thermal%20effects%20on%20materials.pdf
https://pdfs.semanticscholar.org/0cb6/9c4824ea2e23e376e37d4bcd96de761d9702.pdf
Thanks
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